Estimating "common" is quite difficult, but given that there are pre-colonial aboriginal australian burial sites, we can estimate that it either can be traced to Africa or is sufficiently common to not be surprising. There is even evidence (not proof) of neanderthal burial rituals, fwiw.
I always thought that 'ceremonial room' looked more like a sauna than a sacrificial pit. It reminded me of the Roman ruins at Bath more than anything else.
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